While importing with bulkmarcimport.pl, if some of MarcFieldFor* system preference had been set, those fields/subfields will be created, empty or with a "CLI CLI". This happens regardless of the framework setup and potentially overwriting data from the imported record. For e.g., if: MarcFieldForCreatorId "$borrowernumber" 901$l MarcFieldForCreatorName "$userfirstname $usersurname" 901$m MarcFieldForModifierId "$borrowernumber" 901$n MarcFieldForModifierName "$userfirstname $usersurname" 901$o INPUT: 901 $a BIBLO $b 00011605 $o GEORGE OUTPUT: 901 $a BIBLO $b 00011605 $o CLI CLI $l $m CLI CLI $n In this case 901$o was overwritten. The "CLI CLI" comes from the set_userenv call on Script.pm. This can be seen just googling: "CLI CLI" inurl:"cgi-bin/koha" Maybe related to Bug 24906.